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2015-05-30target/user: Only support full command pass-throughAndy Grover
After much discussion, give up on only passing a subset of SCSI commands to userspace and pass them all. Based on what pscsi is doing, make sure to set SCF_SCSI_DATA_CDB for I/O ops, and define attributes identical to pscsi. Make hw_block_size configurable via dev param. Remove mention of command filtering from tcmu-design.txt. Signed-off-by: Andy Grover <agrover@redhat.com> Reviewed-by: Ilias Tsitsimpis <iliastsi@arrikto.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-05-30target/user: Update example code for new ABI requirementsAndy Grover
We now require that the userspace handler set a bit if the command is not handled. Update calls to tcmu_hdr_get_op for v2. Signed-off-by: Andy Grover <agrover@redhat.com> Reviewed-by: Ilias Tsitsimpis <iliastsi@arrikto.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-05-02target/user: Disallow full passthrough (pass_level=0)Andy Grover
TCMU requires more work to correctly handle both user handlers that want all SCSI commands (pass_level=0) for a se_device, and also handlers that just want I/O commands and let the others be emulated by the kernel (pass_level=1). Only support the latter for now. For full passthrough, we will need to support a second se_subsystem_api template, due to configfs attributes being different between the two modes. Thus pass_level is extraneous, and we can remove it. The ABI break for TCMU v2 is already applied for this release, so it's best to do this now to avoid another ABI break in the future. Signed-off-by: Andy Grover <agrover@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-04-19target: Version 2 of TCMU ABIAndy Grover
The initial version of TCMU (in 3.18) does not properly handle bidirectional SCSI commands -- those with both an in and out buffer. In looking to fix this it also became clear that TCMU's support for adding new types of entries (opcodes) to the command ring was broken. We need to fix this now, so that future issues can be handled properly by adding new opcodes. We make the most of this ABI break by enabling bidi cmd handling within TCMP_OP_CMD opcode. Add an iov_bidi_cnt field to tcmu_cmd_entry.req. This enables TCMU to describe bidi commands, but further kernel work is needed for full bidi support. Enlarge tcmu_cmd_entry_hdr by 32 bits by pulling in cmd_id and __pad1. Turn __pad1 into two 8 bit flags fields, for kernel-set and userspace-set flags, "kflags" and "uflags" respectively. Update version fields so userspace can tell the interface is changed. Update tcmu-design.txt with details of how new stuff works: - Specify an additional requirement for userspace to set UNKNOWN_OP (bit 0) in hdr.uflags for unknown/unhandled opcodes. - Define how Data-In and Data-Out fields are described in req.iov[] Changed in v2: - Change name of SKIPPED bit to UNKNOWN bit - PAD op does not set the bit any more - Change len_op helper functions to take just len_op, not the whole struct - Change version to 2 in missed spots, and use defines - Add 16 unused bytes to cmd_entry.req, in case additional SAM cmd parameters need to be included - Add iov_dif_cnt field to specify buffers used for DIF info in iov[] - Rearrange fields to naturally align cdb_off - Handle if userspace sets UNKNOWN_OP by indicating failure of the cmd - Wrap some overly long UPDATE_HEAD lines (Add missing req.iov_bidi_cnt + req.iov_dif_cnt zeroing - Ilias) Signed-off-by: Andy Grover <agrover@redhat.com> Reviewed-by: Ilias Tsitsimpis <iliastsi@arrikto.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-04-15target: fix tcm_mod_builder.pyChristoph Hellwig
Fix a misplaced comma I introduced. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-04-14target: simplify the target template registration APIChristoph Hellwig
Instead of calling target_fabric_configfs_init() + target_fabric_configfs_register() / target_fabric_configfs_deregister() target_fabric_configfs_free() from every target driver, rewrite the API so that we have simple register/unregister functions that operate on a const operations vector. This patch also fixes a memory leak in several target drivers. Several target drivers namely called target_fabric_configfs_deregister() without calling target_fabric_configfs_free(). A large part of this patch is based on earlier changes from Bart Van Assche <bart.vanassche@sandisk.com>. (v2: Add a new TF_CIT_SETUP_DRV macro so that the core configfs code can declare attributes as either core only or for drivers) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-01-06Documentation/target: Update fabric_ops to latest codeNicholas Bellinger
This patch updates tcm_mod_builder.py to add/drop a handful of struct target_core_fabric_ops functions to sync up with the latest requirements to function in target_fabric_tf_ops_check(). Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2014-10-02target: Add documentation on the target userspace pass-through driverAndy Grover
Describes the driver and its interface to make it possible for user programs to back a LIO-exported LUN. Thanks to Richard W. M. Jones for review, and supplementing this doc with the first two paragraphs. Signed-off-by: Andy Grover <agrover@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-10-16target: Remove TF_CIT_TMPL macroAndy Grover
Remove a lingering macro that just hid a dereference. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andy Grover <agrover@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-08-20Documentation: replace strict_strtoul() with kstrtoul()Jingoo Han
The usage of strict_strtoul() is not preferred, because strict_strtoul() is obsolete. Thus, kstrtoul() should be used. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-09-17target: Simplify fabric sense data length handlingRoland Dreier
Every fabric driver has to supply a se_tfo->set_fabric_sense_len() method, just so iSCSI can return an offset of 2. However, every fabric driver is already allocating a sense buffer and passing it into the target core, either via transport_init_se_cmd() or target_submit_cmd(). So instead of having iSCSI pass the start of its sense buffer into the core and then later tell the core to skip the first 2 bytes, it seems easier for iSCSI just to do the offset of 2 when it passes the sense buffer into the core. Then we can drop the se_tfo->set_fabric_sense_len() everywhere, and just add a couple of lines of code to iSCSI to set the sense data length to the beginning of the buffer right before it sends it over the network. (nab: Remove .set_fabric_sense_len usage from tcm_qla2xxx_npiv_ops + change transport_get_sense_buffer to follow v3.6-rc6 code w/o ->set_fabric_sense_len usage) Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-09-17target: Remove unused target_core_fabric_ops.get_fabric_sense_len methodRoland Dreier
There are no callers of se_tfo->get_fabric_sense_len(), so we should stop having every fabric driver implement it. Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-10Documentation: Fix typo in tcm_mod_builder.pyMasanari Iida
Correct spelling "alocate" to "allocate" in Documentation/target/tcm_mod_builder.py Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-12-14target: tcm_mod_builder: small fixupsSebastian Andrzej Siewior
This includes: - remove on _ in "__NAMELEN" in $fabric _make_tport - target_fabric_configfs_init() returns an error pointer and not NULL anymore. Consider that. - replace (!(var_name)) with (!var_name). The extra () are not required - remove #ifdef MODULE. If the code is builtin it needs an init function or the code is useless - put exit/clean functions into __exit Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14Documentation/target: Fix tcm_mod_builder.py build breakageNicholas Bellinger
This patch fixes TFO->release_cmd() and removes legacy pack_lun() usage and new_cmd_failure when generating new TCM fabric skeleton from the tcm_mod_builder.py script. Reported-by: Stefan Bergstrand <stefan.bergstrand@sdsab.se> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14target: header reshuffle, part2Christoph Hellwig
This reorganized the headers under include/target into: - target_core_base.h stays as is with all target-wide data stuctures and defines - target_core_backend.h contains the whole interface to I/O backends - target_core_fabric.h contains the whole interface to fabric modules Except for those only the various configfs macro headers stay around. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-03-23[SCSI] tcm_mod_builder.py: Fix generated *_drop_nodeacl() handlerFubo Chen
This patch adds the missing core_tpg_del_initiator_node_acl() call required by fabric modules for struct se_node_acl->acl_group context shutdown via target_core_fabric_configfs.c:target_fabric_nacl_base_release() -> struct target_core_fabric_ops->fabric_drop_nodeacl() for tcm_mod_builder.py generated $FABRIC_MOD_configfs.c skeleton code. Signed-off-by: Fubo Chen <fubo.chen@gmail.com> Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-23[SCSI] target: tcm_mod_builder.py generated Makefile cleanupsNicholas Bellinger
This patch converts the tcm_mod_builder.py generation script to create a new drivers/target/$TCM_FABRIC_MOD/Makefile and update drivers/target/Makefile, instead of creating+updating a 'Kbuild' filename. It also removes the remaining EXTRA_CFLAGS includes from tcm_mod_build_kbuild(), and converts fabric module generated .c code to us ""-style includes for $FABRIC_MOD_[base,fabric].h Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-14[SCSI] target: Add LIO target core v4.0.0-rc6Nicholas Bellinger
LIO target is a full featured in-kernel target framework with the following feature set: High-performance, non-blocking, multithreaded architecture with SIMD support. Advanced SCSI feature set: * Persistent Reservations (PRs) * Asymmetric Logical Unit Assignment (ALUA) * Protocol and intra-nexus multiplexing, load-balancing and failover (MC/S) * Full Error Recovery (ERL=0,1,2) * Active/active task migration and session continuation (ERL=2) * Thin LUN provisioning (UNMAP and WRITE_SAMExx) Multiprotocol target plugins Storage media independence: * Virtualization of all storage media; transparent mapping of IO to LUNs * No hard limits on number of LUNs per Target; maximum LUN size ~750 TB * Backstores: SATA, SAS, SCSI, BluRay, DVD, FLASH, USB, ramdisk, etc. Standards compliance: * Full compliance with IETF (RFC 3720) * Full implementation of SPC-4 PRs and ALUA Significant code cleanups done by Christoph Hellwig. [jejb: fix up for new block bdev exclusive interface. Minor fixes from Randy Dunlap and Dan Carpenter.] Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org> Signed-off-by: James Bottomley <James.Bottomley@suse.de>